Mild winter good for fruit growers
Caribou farm serves as dwarf tree experimental test site
CARIBOU, Maine — After a mild winter, it should be a good year for apple trees in northern Maine, according to Renae Moran, a pomologist with the University of Maine Cooperative Extension.
That’s not the case in southern Maine and other parts of the Northeast, due in part to the funky winter, said Moran, who works at the extension’s Highmoor Farm in Monmouth.
“Budding started early and reached a stage where they did not have the hardiness to survive. We had a deep freeze in early April that killed flower buds [in southern Maine]. It hasn’t devastated the crop, but parts further south have been devastated.”
Moran was in Caribou on May 7, visiting Circle B Farm’s 650-tree orchard for an open house and apple growing class with owner Sam Blackstone, and to check up on some trees she’s researching.
“This is a good site,” Moran said of the farm’s orchard, at a higher elevation on a hill rising from the Aroostook River across the road. “Fruit trees actually do better in windy sites, because they don’t get as a cold on those cold, clear nights were the warm air rises and the cold air settles. At a higher elevation, the cold air drains away.”
Moran has been running an experiment at Circle B as part of a national project studying cold-hardiness in dwarf trees, which are small, bear fruit early and live relatively short lives.
Dwarf trees work well for home gardeners and farms that want small trees that fruit soon, but they struggle with the cold. Traditional, full-sized trees take up to a decade to fruit, but offer cold-hardiness and last for many decades.
“People tell me, ‘You can’t plant dwarf trees in The County, they’ll die,’” Moran said. “We’re going to find out.”
Seven years ago at Circle B, Moran planted 40 Honeycrisp trees with four different dwarf rootstocks from Canada and New York. Rootstocks are the rooting system a variety of fruit is grafted onto to form a tree.
“How they look?” Moran asked Circle B owner Sam Blackstone as she joined a walking tour. “Not good,” he said. About half of the project’s dwarf trees have died, but others may yet survive, Moran said.
“There are different schools of thought on what an apple tree is,” Moran said. “Some people think it’s the large, old-fashioned big trees, I’m of the other school of thought. A little tree with some deer protection will start to bear fruit quickly.”
For dwarf trees, at least, Moran thinks that Caribou may represented the coldest limit of their range. To the south in Presque Isle, where it’s a tad warmer on average, dwarf trees seem to fare better, Moran said. “And just 20 miles north of here, it’s almost too cold.”
But with hardy varieties and good site selection, Blackstone and other orchardists in cold climates have had success growing semi-dwarf apple trees, as a kind of hybrid option. Semi-dwarf apple trees can grow as tall as 15 feet and retain cold adaptability, while yielding after a few years.
About 400 of Circle B’s apple trees are Honeycrisps, a sweet cold-hardy variety, that are mostly semi-dwarfs. Six of the Honeycrisps are full-size trees. At the time he was planting apple trees, in the early 2000s, Blackstone said his 90-year-old grandfather urged him to have at least a few full-size Honeycrisp, which are now quite big and overall good fruit providers, Blackstone said.
The SAD 1 School Farm in Presque Isle’s 2,500-plus tree orchard has trees from three different rootstocks, two of them being semi-dwarfs and one a cold hardy dwarf.
Blackstone said trees can be grown differently for different uses. In the U-Pick sections of his orchard, the trees are pruned to keep low branches, while other trees are allowed to grow tall and are picked with a ladder.
“I want to keep the branches low for the general public,” he said, standing beside a large 14-year-old honeycrisp tree that has both low and high branches. “I like the 4-year-old kid that can pull the apple right off the tree and a take a fresh bite. I’ve got a customer the rest of my life.”
Old apple trees are found across Maine near homes and road sides, as the remnants of former personal orchards and new trees that have grown from seeds. Among some common heritage varieties planted in Aroostook County were Duchess, Alexander and Yellow Transparent, the latter an early ripening apple originally from Russia that Blackstone also grows a few of.
“Old trees can be renovated. They are worth growing and will produce fruit again,” said John Bunker, a pomologist based in Palermo, Maine, and the founder of Fedco Trees.
“Even if they look decrepit, they respond to pruning and some fertilizer or compost,” said Bunker. “These varieties were grown because they are very good varieties.”
